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From: Jun Han <junhanece@gmail.com>
To: "dev@dpdk.org" <dev@dpdk.org>
Subject: [dpdk-dev] DPDK Latency Issue
Date: Thu, 22 May 2014 18:44:00 +0200	[thread overview]
Message-ID: <CAGeT4P+2shS+goNQbs1MH0ye+8OdndAG-J6qb3Gjkeht+XKH7Q@mail.gmail.com> (raw)

Hi all,

I measured a roundtrip latency (using Spirent traffic generator) of sending
64B packets over a 10GbE to DPDK, and DPDK does nothing but simply forward
back to the incoming port (l3fwd without any lookup code, i.e., dstport =
port_id).

However, to my surprise, the average latency was around 150 usec. (The
packet drop rate was only 0.001%, i.e., 283 packets/sec dropped) Another
test I did was to measure the latency due to sending only a single 64B
packet, and the latency I measured is ranging anywhere from 40 usec to 100
usec.

I do not understand why this is so slow. Can someone explain the reasoning
behind this phenomenon?

Thank you so much!

             reply	other threads:[~2014-05-22 16:43 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-05-22 16:44 Jun Han [this message]
2014-05-22 17:06 ` Shaw, Jeffrey B
2014-05-26 19:39   ` Jun Han
2014-05-28 12:58     ` Jun Han

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